A vertical-brushing electric toothbrush. Forward and reverse oscillations of a head (9) are implemented by means of a spatial transmission mechanism, to simulate a vertical brushing action process of real manual tooth brushing. A spatial gearbox is provided in the toothbrush, and the gearbox comprises an upright cam (2), a main support (3), a sliding block (4), a rolling ball (5), a sliding block limiting cylinder (6), an inverted cam cylinder (7), and a gearbox housing (8). The upright cam (2) is the input end of the gearbox and is sleeved on a rotating shaft of a motor (1)； the inverted cam cylinder (7) is the output end of the gearbox and is connected to the head (9) of the electric toothbrush； the upright cam (2) is provided with a slot (21), and the upright cam (2) cooperates with the rolling ball (5) by means of the sliding block (4) to drive the inverted cam cylinder (7), to convert the unidirectional rotation of a spindle of the motor (1) into directionally-variable oscillations of the head (9), thereby implementing spatial motion conversion and speed change. The addition of the gearbox achieves, in a case of a limited radial size, fixed indexing of input and output rotation angles in the coaxial or axial parallel direction, and the output characteristic of keeping the frequency constant but increasing the torque multiple.L'invention concerne une brosse à dents électrique à brossage vertical. Des oscillations avant et arrière d'une tête (9) sont mises en oeuvre au moyen d'un mécanisme de transmission spatiale pour simuler un processus d'action de brossage vertical de brossage des dents manuel réel. Une boîte de vitesses spatiale est disposée dans la brosse à dents, et la boîte de vitesses comprend une came verticale (2), un support principal (3), un bloc coulissant (4), une bille de roulement (5), un cylindre de limitation de bloc coulissant (6), un cylindre de came inversé (7), et un logement (8). La came verticale (2) est l'extrémité d'entrée de la boîte d
